For 3 days i've had very thick yellow goo when i cough. chest congestion and at night way way too much spit. never had this before no other symptoms.

URI: Symptoms may suggest upper respiratory infection which is more commonly viral but could be bacterial. Decongestants, cough syrup and fluids will help.

NEED A CHECK UP: You need to see your doctor to have a check up.Yellow goo is of no concern.But chest congestion and too much spit needs to be evaluated.You may have acute bronchitis or just a viral upper respiratory infection.In meanwhile drink plenty of fluids and take some over the counter cough medicine till you see your doctor.

See your doctor: It's always a tough call whether or not someone needs antibiotics based on symptoms alone. Even though the mucous is yellow, it doesn't necessarily mean there's a bacterial infection. A doctor needs to take a look at your vitals, sinuses, listen to your lungs, possibly check your oxygenation and /or a chest x ray to determine the best treatment for you.